Small drivers vs big drivers


Hi,
I have a question that is always in my mind recently. I see some speakers with small  drivers (5-9 inches) that is reviewed to be able to throw out big sound stage and go down to 18hz-20hz. Some other speakers with big drivers (10-15 inches) though are commented to have 'big sound stage' but can only go as low as 30-35hz. 

To make the situation more complicated, some speakers have small drivers but there are many of them. Can many small drivers be compensate for the size limitation?

I don't know which specs determine a wide sound stage and the ability to reach low frequencies.  What is the pros and cons of each design?

Thank you!

Huy.
Ag insider logo xs@2xquanghuy147
Despite multiples of 7" or 8" drivers having the same radiating surface when calculated mathematically, there's something about a 12" or larger that just sounds better.  Designers went to smaller drivers to make speakers narrow, for ergonomic and stylistic reasons; there's something really special though about a wide baffle speaker that can accommodate a big woofer on the front.
Adding to @twoleftears :

The 2.5 way speaker is a little miracle of efficiency, space and capability.

Two 8" drivers are still only the radiating surface of a 10" or so, but the increased efficiency, and reasonably extended bass output make them superbly enjoyable compromises.

Best,
E
@twoleftears

+1. A 12” or larger woofer can pressure up the room much like a real kick drum would do. The difference is very noticeable. The tendency of speakers with smaller woofers is to generate the lowest frequencies through port tuning which gives a muddy sounding kick drum, as the transient response is smeared by group delay. The frequency response on small multiple woofer speakers can be sometimes equaled to that of a large woofer by clever use of ports to plumb the subsonic depths but the time smearing from porting leaves one with the impression of a kick drum that sounds a bit like a bass guitar - it hums or resonates rather than sounding explosively punchy.

Large woofers really make a kick drum sound realistic and much more distinctive from bass guitar despite sharing similar frequencies.
@shadorne

Did you mean sound realistic, or feel realistic?
I ask because I am always curious how much we actually listen through our skin than our ears.
@erik_squires

I think we hear it but you are right in the sense that it isn’t really a change in the sustained note of the kick. It isn’t because there are more lower frequencies present - more a time coherence thing - the slap of the head with the kick pedal is matched by a very low frequency room compression that the ears “feel” more than hear - like descending in an aeroplane but infinitely faster. It is very useful to clearly distinguish kick from bass guitar. A timbral effect caused by a time coherent transient.

You won’t get this effect from a ported subwoofer but you can get it from a sealed one like a JL sub.

There is a huge amount of detail in the bass range - most bookshelf ported designs can sound enjoyable but fail completely at conveying this detail or texture. All Headphones fail too. Maybe feeling does have something to do with the effect - our bones would pick this pressure or LF up too.